1. Field of the Invention
The present invention relates a passenger distinguishing apparatus, and more particularly, to a passenger distinguishing apparatus that includes a damper for improving durability of a sensor and for increasing a coupling force of the sensor while solving assembling tolerance occurring when assembling the sensor.
2. Description of the Related Art
An air bag device is a device for protecting passengers within vehicles by absorbing a physical impact occurring when vehicles collide using elasticity of an air cushion and is classified into a driver seat air bag device, a passenger seat air bag device, and a side air bag device.
When a gas is injected into the air cushion upon collision of vehicles, the air cushion inflates in a high speed in order to protect a passenger, and thus when the passenger seated in a passenger seat is a child or an adult having a light weight, due to an impact by inflation of the air bag cushion, the passenger may be injured.
Therefore, it is necessary to determine inflation of the air bag cushion in consideration of the passenger's weight, and thus North America countries have a separate legal standard for limiting inflation of an air bag cushion according to a passenger's weight measured in a passenger seat in various conditions.
Therefore, an air bag apparatus manufacturer should provide means for satisfying these conditions in order to improve a performance of an air bag device and to export to North America countries. For this, conventionally, by providing four or more sensors in the passenger seat, when a passenger is seated, a passenger's weight is measured, and by comparing the sum of load values measured in sensors with a reference value, inflation of the air bag cushion is determined.
FIG. 1 is a cross-sectional view illustrating a passenger distinguishing apparatus in the prior art.
Referring to FIG. 1, a lower bracket 5 for mounting a passenger seat (not shown) is fixed to a floor within a vehicle. An upper bracket 10 for assisting mounting of the passenger seat is disposed at an upper part of the lower bracket 5. In order to effectively support the passenger seat, the lower bracket 5 and the upper bracket 10 are generally disposed at four corners of a lower part of the passenger seat. A sensor 15 for detecting a weight of a passenger seated in the passenger seat is disposed between the lower bracket 5 and the upper bracket 10.
Specifically, an upper end part 15b and a lower end part 15a of the sensor 15 are vertically protruded, and threads 15c and 15d are formed in the upper end part 15b and the lower end part 15a. Fastening holes 5a and 5b for inserting and bolt-fastening the lower bracket 5 and the upper bracket 10 are formed in the lower bracket 5 and the upper bracket 10. In the sensor 15 disposed between the lower bracket 5 and the upper bracket 10, when the upper end part 15b and the lower end part 15a of the sensor 15 are inserted into and protruded from the fastening holes 5a and 5b, respectively, nuts 20a and 20b for tightening and fixing the upper end part 15b and the lower end part 15a, respectively of the sensor 15 are disposed at a portion corresponding to the rear surface of the lower bracket 5 and the upper bracket 10.
However, as already known, when producing parts, almost all parts have somewhat tolerance and in a product having an assembling process, in order to reduce inconvenience upon assembling, the product is manufactured to have somewhat tolerance. Similarly, when mounting the sensor 15 in the lower bracket 5 and the upper bracket 10, the sensor 15 is also manufactured to have predetermined tolerance, however assembling tolerance of the sensor 15 may cause the result contrary to an installation purpose of the sensor 15 for accurately detecting a weight of a passenger seated in the passenger seat. In other words, by putting predetermined assembling tolerance in the sensor 15, if assembling tolerance is not absorbed in an assembling process, due to a shaft load, or a stacking load such as a moment, error occurs, in the sensor 15 designed to measure a vertical load, or due to a continued vibration occurring when operating the vehicle, the sensor 15 has a clearance and thus there is a problem that durability of the sensor 15 is influenced.
In order to solve such a problem, conventionally, as shown in FIG. 1, a pair of dampers 25 for enclosing an end part of the fastening hole 5b are disposed in at least one of the upper end part 15b and the lower end part 15a of the sensor 15, and in order to prevent shaking of the damper 25, a pair of sleeves 30 closely contact with the damper 25.
However, because the damper 25 and a sleeve 30 disposed to absorb assembling tolerance should be provided with a pair in each sensor 15, when it is assumed that the sensors 15 are disposed at each of four corners of the passenger seat, the damper 25 and the sleeve 30 should be provided with eight pieces and thus there is a problem that a cost greatly increases.
Further, as a height of a pair of damper 25 and sleeve 30 greatly increases, the screw thread 15d tightened and fixed by the nuts 20a and 20b reduces and thus there is an additional problem that a fixing force of the sensor 15 reduces.